Braves Rotation Excels Thanks to a Low BABIP

The Braves have the lowest ERA in the majors thanks to a .235 batting average on balls in play. But is it sustainable?

The Braves have jumped out to the Majorsâ€™ best record at 12-2. After their 10-game win streak, Atlanta leads the league in home runs, staff ERA and is third in slugging percentage. Basically, whenever the offense isnâ€™t clubbing you to death with homers, the pitching is preventing you from scoring any runs. A lethal combination so far.

But there is reason to believe that the Braves pitching is just very good rather than best-in-the-league good. Currently the Braves staff leads the majors by a wide margin with a 1.83 ERA; the second-best team, the Red Sox, has a team ERA of 2.64. As is usually the case when an entire staff pitches like vintage Pedro, there has been a bit of luck involved.

The Bravesâ€™ FIP (fielding-independent pitching) is at 3.25 â€“ still very good, but fifth in the league. Some pitchers can consistently outpitch their FIP, but it is rare. And such a wide gap between ERA an FIP is especially due for regression. The reason the Bravesâ€™ ERA is so much lower than their FIP is due to excellent luck on balls in play.

A BABIP Story

Batting Average on Balls in Play (BABIP) typically is around .300 for the whole league. The theory is that once a batter has put the ball into play, the pitcher has no control over whether the ball will be converted into an out. This is what FIP measures. Now, this is one extreme of the spectrum. It is more likely that pitchers have a little bit of control once the ball is in play, but not total control as ERA would suggest. It is probable that some pitchers can consistently induce weaker contact, thus producing lower BABIPs from year to year, but in general, around .300 is league average.

The Braves currently lead the majors in pitching BABIP with a .235 average. They have clearly been the beneficiaries of some luck on balls put into play. Now, there are some factors that can contribute to low BABIP, namely excellent defense. Andrelton Simmons is one of the best defensive shortstops in the league, and the outfield of the Uptons and Jason Heyward has good range, but those four alone arenâ€™t enough to plausibly maintain the staggeringly low rate of balls in play that fall for hits.

Three of the Bravesâ€™ starters are posting BABIPs under .220, which is incredible, and incredibly lucky. Paul Maholm (.212), Tim Hudson (.220) and Kris Medlen (.219) have all pitched excellently, but are primed for at least some regression over the course of the season.

Of the three, Hudson seems the most likely to induce weak contact and therefore have a lower BABIP, since he is a sinkerballer who produces a ton of ground balls. His career mark of .278 fits this theory, as it sits a little south of the .300 range typical for pitchers. Interestingly, heâ€™s been even better (or even luckier) late in his career: the last time he posted a BABIP higher than .273 over a full season was 2007. (This statistic does not include 2009, when he threw only 43 innings.) Perhaps as Hudson got older, he relied more on his sinker, inducing more ground balls than line drives. Or maybe heâ€™s just riding a six-year lucky streak, in which case he should find time to play some roulette in Las Vegas.

Maholm is an interesting case as well. He has not allowed a run yet in 20 innings across three starts, and is obviously not going perform like this for the whole year. Needless to say, he has gotten extremely lucky on balls in play, with that .212 mark, which is 10th-lowest in the majors for starters. It is well below his career mark of .305. But like Hudson, he appears to be getting better with age as well.

Maholmâ€™s BABIP has decreased every year since 2010. Jonah Keri detailed on Monday how Maholmâ€™s pitch selection has changed, particularly his change-up and slider. Maybe his new approach has something to do with his ability to get balls in play to fall for outs.

In that three year span, Maholmâ€™s strikeout rate has also risen every year, so heâ€™s making batters miss more than ever too. This seems likely to correlate with his newfound propensity to induce weak contact. If not, and itâ€™s all simply lucky variance; he should probably join Hudson on that Vegas trip.

Medlen is a tougher case, as he has a much smaller sample size due his age and injuries. It is worth noting that even during last seasonâ€™s incredible run of starts, Medlen posted â€œonlyâ€ a BABIP of .261, still below the league average, but nowhere near his current .219. So if last yearâ€™s performance was the absolute best-case scenario for him (and if itâ€™s not, lock him up to a long-term contract immediately), it is simply impossible that he could maintain such a low BABIP over a whole season.

This all isnâ€™t to say Iâ€™m down on the Bravesâ€™ pitchers at all. I think they will end the season as a top ten, likely top five staff. Mike Minor in particular has been excellent dating back to last June, and his stuff has carried over this season. And this does not even factor in Brandon Beachy, who may take over from the struggling Julio Teheran when he returns from Tommy John surgery this summer.

But it is interesting to see exactly how the Braves grabbed the majorsâ€™ best record, and realistically analyze whether they will be able to maintain this level of production. So far, at least some of their success on the pitching side is due to luck.